Conventional computerized devices frequently require the ability to interoperate with individual users using one or more user operated input-output devices. By way of example, a conventional computer system such as a personal computer or workstation typically includes one or more user operated input-output devices, such as a keyboard and a mouse. The keyboard and mouse allow a user, via manipulation of input mechanisms on the keyboard (e.g., pressing of keys) and/or the mouse (e.g., pressing of buttons and movement of mouse), to input information into the computerized device. In addition, in some circumstances, a computerized device is able to output information to a user operated device in order to control functionality within the user operated device. As an example, a computer system can provide signaling information to a keyboard device in order to activate or deactivate certain function keys within the keyboard or to enable or disable (e.g., turn on or turn off) light emitting displays or diodes within the keyboard device in order to signal the user of certain events such as the enablement of a CAPS LOCK, SHIFT LOCK or NUM LOCK key.
Data communications that take place between conventional user operated input-output devices and computerized devices are typically carried out by rather simple signaling protocols over a dedicated interface. As an example, when a user depresses a specific key on a conventional keyboard, a microprocessor or other hardware or circuitry within the keyboard translates this key press into a specific key code associated with that key. The processor then transmits this code as a signal over the communications medium such as the keyboard cable or a wireless link that couples the keyboard device to a dedicated keyboard interface within the computerized device. Since each key on a keyboard is assigned a unique key code, the computerized device receiving a series of key codes corresponding to key presses provided by a user is capable of translating these codes into a predetermined alpha numeric text code such as the American Standard Code for Information Interchange (ASCII). The circuitry then sends electrical signals representing these keystrokes to the computer system. A software application receiving such codes from the keyboard interface within the computerized device can interpret this information as input from the user. Other devices such as a mouse or joystick or gaming control device can operate one or more potentiometer that circuitry within the user operated device samples as a rapid frequency. Each sample can be transmitted to the computer system to provide a continuous stream of input from the user into the computer system.
Certain other conventional technologies provide secure communications between user operated devices such as telephones. In one such conventional technology, a key issuing organization such as a government entity (e.g., the National Security Agency) issues (i.e., provides) a physical key device to an owner/user of a secure telephone unit (STU). The key device issued to the user of the secure telephone unit includes a microchip that contains an embedded cryptographic key specifically assigned to that user. When the user is engaged in a non-secure telephone conversation using his or her STU with another user that is also talking on a similarly configured STU, each user can verbally agree to enter into a secure voice conversation. Upon doing so, each user can insert his or her key device into the STU. Each STU reads the cryptographic key information from the microchip embedded in the key device for that user in order to provide secure communications between itself and the other STU under control of the other user. Specifically, upon each user inserting and activating (i.e., turning) the key device within that user's respective STU, each STU begins to listen to and rapidly digitize the voice of the respective user of that STU. Once digitized, the STU can apply the cryptographic key information from that users key device in order to encrypt the digitized version of the voice of the user for that STU. Once encrypted, the STU can transmit the key encrypted voice to the other remote STU at the other end of the telephone line connection. The remote STU can receive the encrypted voice and can use local cryptographic key information (e.g., received from the local users key) to decrypt the encrypted voice received from the remote user. Since the key information in each users key device is related, this information allows the establishment of a successful secure communications session. In this manner, each STU can engage in an digitized encrypted voice communications session allowing each user to talk securely without the fear of the digitized voice being intercepted and deciphered by a third party (e.g., a malicious individual who may be wire tapping the telephone conversation).